基于能量原理的隧道下穿既有水电站爆破振动响应研究

Study on Blasting Vibration Response of Tunnel Undercrossing Existing Hydropower Station Based on Energy Principle

本文依托东南地区炉坪隧道下穿山连水电站工程,基于能量原理对爆破施工能量转换过程进行深入研究,以推导水电站爆破振动安全判据。根据工程实际及相关规范要求确定爆破振速安全阈值为0.5 cm/s,小于理论计算爆破最大振速。根据安全振速及萨氏公式计算隧道爆破最大装药量,对下穿段进行爆破参数优化设计,并建立三维数值计算模型,对水电站爆破动力响应开展研究。结果表明:采用优化后的爆破参数进行爆破对山连水电站总体上振动影响较小,爆破振速基本满足规范要求,但对水电站靠近隧道进口侧顶部及边墙影响较大,需采取应对措施;水电站变形沉降较小,基本可忽略不计。

Based on the project of Shanlian Hydropower Station under Luping Tunnel in Southeast China,this paper conducts in-depth research on the energy conversion process during the blasting construction based on the energy principle,so as to derive the safety criteria for blasting vibration of the hydropower station.According to the actual situation of the project and relevant specifications,the safety threshold of the blasting vibration velocity is determined to be 0.5 cm/s,which is far less than the maximum blasting vibration velocity calculated theoretically.Then,the maximum explosive charge for tunnel blasting is calculated based on the safe vibration velocity and Saskatchewan formula,and the blasting parameters for the undercrossing section are optimized.A three-dimensional numerical calculation model is established for the blasting parameters,and the dynamic response of the hydropower station is studied.The research shows that:using the optimized blasting parameters has a small impact on the vibration of the Shanlian Hydropower Station,and the blasting vibration velocity meets the specification requirements,but the tunnel blasting has a significant impact on the top and side walls of the hydropower station near the tunnel entrance,and countermeasures should be taken.The deformation and settlement caused by the hydropower station are relatively small and can be basically ignored.